Automatic lubrication system



p 21, 1936 w. K. HAWKs ET AL AUTOMATIC LUBRIC'ION SYSTEM Filed Jan. 5,-A 1951 Tren ATToNEYs Patented Apr. 2l, 1936 PATENT v`OF F I CIE Creek, 'Mich., assignors, by mesneA assignments, to The Farval CorporatiomCleveland, Ohio, a

corporation of vOhio Application January 5, 1931, SerialNm 506,602

'22 Claims.

The present inventionpertains to a novel automatic lubrication system, and the Iprincipali-object is-toprovide a system wherein a series of measuring valves applied toa number of bearings may be automatically operated at predetermined intervals.

YThe measuring valves used in the present system are preferably ofy the type: which receive'the lubricant under pressure and from which the lubricant is vdischarged into theebearings under pressure by means of the same or` anotheriiiuid. The invention therefore embodies a pump for supplying the lubricant or grease. andganother pump for supplying the otherfluid or oil.

`The pumps are electrically driven, and the action of the systemis initiated by a time switch which sets'the grease pump in motion. When the valves have been lled with grease, a A,mechanism associated with one of the valves stops, the grease pump and starts the other pump whereby the grease content of the measuring valves isdischarged into the bearings.

The last mentioned valve is; known as the control valve and is preferably the lastl in the series or that disposed at the ldischarge ends of the fluid lines. Pressure relief valves are inserted ing-the lines directly in advance o-f the control valve land are adjusted to open the-lines o-nly atpthe maximum pressures inten-ded for the fluids. Consequently the valves precedingthe controlvalve must receive the fluids at the `maximum pressures intendedv therefor'before the relief f valves will fopen. :Thusfthe control valve will not be supplied withfluid and will not function to vcontrol the electrical system Vuntil the preceding valves have received fluid at the intended pressures. The failure of the electricalsystem-'to operate for this reason vmay readily bediscovered or indicated by anysuitable-meansfffor the purpose.

The invention vis fully disclosed by way of example in the following description and-in the accompanying drawing in which the 'single'gure is a'diagrammatic view of an apparatus-constructed according to the invention, illustrating 4ber isdeiined by a partition #beneath-which is formed a valve chamber 5 tted'witha-sliding piston valvel S. An outlet nipple 'I exten-ds (Cl.V 184-7 fromthe chamber 5 and is adapted for connection to Athebearing in any suitable manner.

,'The partition has an intake port 8 andan outlet` porte 9 connecting thevpiston chamber to thevalvechamber. Further, a lubricant intake 5 passage I Il communicates with the valve chamber 5 and iS,k governed by Vthe valve 6 with respect to its communicationwith the chamber 2 through the port`8. The valve'G is so dimensioned as to obstruct the intake port 8 in one position, 10 While permitting communicationbetween thedischarge port 9 and the outlet-nipple 'I through the chamber 5; and in another position to obstruct the passage in nipple I while opening the port 8 to the passage I0 so that the chamber 2 may rel5 ceive lubricant beneath the piston 3. A spring I I behind-the valve 6- normallyhol-ds Ythe valve in the formerv position. The measuring valve isoperated byiirst filling the chamber 2 beneath the piston :with lubricant through Ythe passages I0 2O and 8 and then applying afluid lpressure upon the piston whereby the valve 6 is shifted to discharging position and the lubricant beneath the piston 3 expelled through theport 9, chamber 5 and outlet l. Q:

The lubricant will hereinafter be identiiiedas grease, and the uid pressure medium for expelling the lubricant will be referred to as oil, merely for the purpose of illustration andconvenience in description. 30

The grease supply is contained in a suitable reservoir `(not shown) from which it is discharged by means of a pump I2. The pumpin turn is driven at intervals by an *electric motor I3v as willv presently be described. In like man- 35 ner, the oil is contained in a reservoir (not shown) and is discharged by means of aV pump -I5 driven by an electric motor I6.

A main grease line I'I is connected by branches I 8A to'the passages I Il of the several measuring 40 valves. The end of the line constitutes a branch I 8 leading toY the final valve I9 of the series. Between the final valve I9 and the preceding valve, a relief valve 20 isl inserted for a purpose which will presently appear. 45

In a similar fashion, a main oil line 2I is connectedI by branches 22 to the `piston chambers 2 of the'several measuring valves. The Yend 22 of this line is also formed as a branch leading to the chamber 2 of the final valve I9. Between the 50 end 22' and the preceding branch 22,V a-check valve 23 istinserted in the line. This -valve obstructs iiowV in the vdirection towards'thenal svalve. Oil is-supplied to the final valve -through a by-pass 24 around the checkvalve 23,'and inthe 5 by-pass is inserted a pressure relief valve 25, similar to the valve 2D, also for a purpose which will presently be described.

The flow to the lines I1 and 2I is controlled by a shuttle valve or two-way line valve including a chamber or cylinder 26 at the intake ends of the respective lines. A line 21, extends from the grease pump I2 to one end of the cylinder 26, and a similar line 28 extends from the oil pump I5 to the other end of the cylinder. In the cylinder 26 is slidably mounted a shuttle valve member comprising a rod 29 of considerably smaller diameter than the inner wall of the cylinder and formed at its ends with heads 30 and 3I which have a sliding t in the cylinder. When the grease pump is in operation, the pressure created thereby displaces the shuttle valve member to a position where the head 36 lies between the lines I1 and 2 I, thereby permitting free communication between the lines 21 and I1, and where the head 3l lies between the lines 2I and 28 and obstructs `communication therebetween. Strainers I1 and 2| are preferably inserted in the lines I1 and 2I respectively between the cylinder 26 and the flrst valve I.

When the valve chambers 2 are thus being filled with grease beneath the pistons 3 thereof, the oil disposed above the pistons is displaced by the upward movement of the latter. In order that this displacement may occur Without obstruction, a return line 32 extends from the cylinder 26 to the oil reservoir. This line is so positioned as to be in communication with the line 2I when the grease pump is operating, whereby the oil displaced from the chambers 2 is returned through the branches 22, line 2I, cylinder 26 and line 32 to the oil reservoir. The oil returning from the final valve I9 avoids the pressure relief valve 25 by opening the ball check valve 23.

In a somewhat similar manner, a return line 33 extends from the cylinder 26 tothe grease reservoir and is in communication with the grease line I1 when the oil pump is operated, but is not entirely identical with the line 32 in function, inasmuch .as grease is not ordinarily returned to the line when oil is supplied under pressure. The opening of line I1 to line 33 is to eliminate the possibility of trapped pressure in the grease line while the valves are being discharged by the oil pump.

The rod 29 carries an intermediate head 29 positioned to separate the lines I1 and 33 from the lines 2l and 32 respectively, thereby avoiding the mixing of oil and grease in the space between the heads 30 and 3|.

A pressure relief valve 34 is connected across the lines 21 and 33 and is set at a pressure equal to or slightly greater than that with which the grease is intended to be delivered to the line I1, so that if the pump should develop an excessive pressure, the excess will be relieved through the line 33 to the grease reservoir. In like manner, a pressure relief valve 35 is connected across the oil lines 28 and 32 and is set at a pressure equal to or slightly greater than that to be applied to the oil for expelling the grease beneath the pistons 3, so that any excess pressure will be relieved through the line 32 to the oil reservoir.

The pressure relief valves 26 and 25 are set at the pressures with which the grease and oil respectively are to be delivered to the valve I9. Consequently, the nal valve I9 (which governs the operation of the system as will presently appear) does not operate until each of the preceding valves has received the full grease and oil pressures intended for the system.

The motors I3 and I6 are operated at predetermined intervals by means of a clock 36 which closes a switch 31 in the electricalsystem at such intervals. The grease pump motor I3 alone operates immediately on the closing of the switch 31. Adjacent the nal valve I9 are disposed a normally open limit switch 38 and a normally closed limit switch 39. A plunger 4l! extends from the piston 3 of the final valve I9 into the space between the switches 38 and 39. The plunger carries at one side a cam 4I adapted to engage and close the normally open switch 38 when raised to its upper limit by the filling of the final valve chamber with grease beneath the piston.

The effect of closing the switch 38 is to break the circuit supplying the motor I3 with current and to close the circuit of the motor I6, whereupon the oil pump functions, lls the chambers 2 above the pistons 3 and discharges the grease to the bearings in the manner already described. When the piston 3 has displaced the grease from the chambers 2, a cam 42 at the opposite side of the plunger 40 opens the normally closed switch 39 as illustrated in the drawing. The effect of opening the switch 39 is to break the circuit to the oil pump, so that both pumps are now idle and the system is inoperative until the grease pump motor circuit is .again closed by the time switch 31.

It will be evident from the foregoing that the measuring valves connected to the several bearings are simultaneously operated at predetermined intervals for which the clock 36 is set. An important property of the invention is that the final valve I9, which governs the operation of the grease and oil pumps as described, is not operated until all the preceding valves receive grease and oil at the maximum desired pressures. This condition is brought about by the insertion of the relief valves 20 and 25 immediately in advance of the final valve I9, so that the maximum permissible pressures of grease and oil are assured in the measuring valves I before the final valve I9 is actuated. The same pressures are assured in the final valve by reason of the opening of the valves 20 and 25 at these pressures before the. valve I9 is lled with either fluid. Consequently, there is no possibility of discharging grease into the bearings at lower pressures than intended.

In the event that either of the lines I1 or 2I becomes obstructed, the development of excessive pressures will be prevented by the relief valves 34 and 35 as already described. The final valve I9 will in such a case fail to operate, and hence the electrical system will not operate. The failure of the electrical system would readily be observed and in fact may be detected by the use of a signal light or a pressure recorder operatively connected to the final valve I 9.

The electrical system may be of any suitable character capable of operating the motors I3 and I6 from the plunger 40 in the manner described. The system illustrated herein is merely incidental to the invention and is not intended to limit the invention thereto, inasmuch as numerous electrical systems, operating on direct or alternating current, for accomplishing the described functions may be designed by one skilled in the art. The system shown in the drawing will now be described merely for the purpose of illustration.

Electrical circuit An alternating current circuit represented by the conductors 5D and 5I and controlled by a line switch 52 energizes the primary winding 53 of a transformer associated withlthe clock'36. H1'1Yhe secondary I winding154 ofv `.the clock. transformer energizes the ieldf 55 andl operates fthe Vclock which in turn closes Vthe switchl'311 atepredetermined intervals as already stated.

In .the `'system 'shown herein, the' motorsr`13 and I6are"direct current shunt motors wth'fstarting resistances, although an electrical ...system 'in keeping with thea-invention may readily'f-be designed for alternating current motors if*y desired.

rI`-heI direct current enters at a line conductorfiA and passes vthrough the line switchfB .tolaqconductor'B, ycontinuing from the .point C through conductor' 56. and switch"31' when closed, along conductor'51 to a manual switch 58vwhichmust be"closed to'render 'the circuit. operative; thence along conductor.v 59through a greasegmotor vcontrolling contact C, thencef through ana overload relay B01 to the solenoid" F .of a `magneticrswitchs 1 thencediverging at pointE into-a conductorifl to the switchfB. and. other side A' of'ithexline. Theflow of current throughisolenoid' F"closes a sWitclf-F to which is linked a-maintaining switch The shuntfeld of the motor I3. isnowcom- Ll prised'in a :circuit with the following parts Line A,.sWitch B, conductori63 leading to the-winding Grof the. overload relay switch'fllxand :then-ce through the switch F to the-greasemotor'eld conductor 64 returning by the common returnrtBS l to. a conductor leading totheswitch Briand line A. lThe armature currentwis ytaken `from the conductor .63 at its point 'off intersectionfwith the conductor 64, ilowsY through the starting-resistance61 and grease motor armature :conductor 68 returning byxthe commonreturnf B5. s. Where they current passes from resistanceffltocconductor 68, it is branched off toavcoil-i-Hzand'then ows :through-conductors'. 69 and fill-cto pointf"E and thence'fto line'A throughthe path already described. C'oil H is thus energized andcloses a switch :H21l which cuts out the:startingzresistance 6 1 permittingY the current to fflow'. from vconductor 63 through'this vswitch to conductor-x68.

' Thergrease 'motor vcircuit .as'thus described 12dependson the closing ofatheclock switch31, which however is Iclosed fon-ly for'an instant. AAnzauxiliaryy circuit passes Ithrough. the switch sF2 Yand maintains the `motor in operation independent`y of..the*switch 31. This circuit,compriseslthefollowing. parts: Line A, switch' B; coil"Gs,-swit'ches F' and Fxconductor 1I, switch'ES, 'conductor'.59, .switcl1"C, relay' 60, coil`F, pcintE,.conductor'6l, switch" B andline A.

fWhen the measuring valveshave beenlled with"grease,. the pistons 3 thereof are raised to the. uppermost limit. The raised positionof the piston in thefnal va-lve 'I9 causes the cam" "4I to close'the normally openv limit switch 38. 4A circuit through this' switch comprises"fthe` following:parts: Line A, switchB, conductor'B to point C', conductorl 12 through the limit switch, `through a common return 13, through-an .overload relay switch P for the `oil ,motorcircuito-sole- :noid..L, point E, conductor 6|,switch Band line A'. .The passage, of current throughsolenoid L Icloses Iswitches L Vand L2 andopensthegrease :motor :maintaining contact C, whereuponz-the grease. motor circuit is brokenfandy the .grease motor stopped. An oil motor circuit-is nowv established through ,the following Line A, switch y B, conductor-*163, conductor 14, lwinding Pwof vthe 4overloadrelay P, switch L', conductor 15,-; conzductorf' to the oil motor field, returning. bythe common/return 11 to conductor266,-switchBarid linefA. From conductor 15,::the current-:falso flowsE through-k.a-.fstarting.resistance l18 "for .the cih-pump motor; passing l'through conductor 19 tofflthe oil .-motor .armatureAl and f returning Fby the commonwreturnf 1 1. i"-\Proceedingf from the starting `nsistance flfltheA current v"also ows through coiD-R.andzconductor-JO to switchfB and line A', thereby closing the switch R-andrshort normal-wfopen position. The :opening of Y this switchwould :2de-energize .the coil L f and open the-.switchlL.comprised .in the. oil motor circuit, so...that.-;,the;latter. .circuit would: be broken. But beforenthei'switch' opens, a simultaneous circuitazthroughwhe coil L risrmaintainedthrough the following parts z` .I linezA., `switch lB, .conductors 63 .and.:14,.coil P', switches L- and'v L2, .conductor 80 .to` the :switch `39, `returning byifthe; common re-l turng13, koverload relaygswitch P; coil L, point E, conductor B I,switch B.and,.line=A. The-latter circuit-...maintains othe.coil.Lw-.energized and .'the switchesi L .zand L2 'closed :after v.the switchv 38 opens; by the-initiak retracting-movement of;;the cam 4| by the movement of the piston 3 under pressure: fromai-the-roilt-pump. Thenauxiliary Eor maintaining circuit-l forthe oil-pump-motor, howevergisndependentron'fthe switch-39. 'Wl/hen the nal .va-lve I9 is'vfully';discharged, the cam 42 opensIther-normally4 closed.- limit switch 39- and breaksthe oilfmotor-circuit. ."The system-isnow idlernntilfsthe switch" 31 iis again lclosedby `:the clock-whereupon:another -cycle such as that described:takeszplace.

s Although 'the.. invention is herein described; yin connection-ewitha Ilubricatingfsystem, -it is g also applicablewfon a .isimilarfdistributionf ofrmeasured quantitiesgof anyotherfluid. "Suchfother uses are contemplated-within fthef scopefwof .the annexed claimsfwhichfrefer to alubricating gsystem merelyy by: way ofexample.

Although a specic embodiment of the invention has. been illustratedand described; it will be understoodfthat various:'alterations in ,the details of-construction maybe made without 4departing fromithei-scopeiof the-,.-inv.ention, 4as indicated b the appended claims.

4 ,Whateweclaim-fis 1.;-An\.fautomatic lubricating-.system comprising avseries of measuring-valvesfafffeed line. common thereto.' a.pressure Aactuatedf-piston ineach valve, avpu'mp for ycharging-said .li-ne, a motor for-drivingasaid pump, and means vconnected directly-to .the.pistonin the final-valve offthefseries -forfcontrollingthe-supply of current tosaid motor.

l-ZefAn automatic lubricatingfsystemcomprising a series of rneasuring=valves; a feed line common thereto,;. a KHpu-rnpf-for charging saidI line,..a': motor fordriving.said.pump, and a pressure relief valve interposed: in .said line directly infadvance of the iinalvalvein the-series, Wherebysaidnnal valve is Opera-tive only. .on the.v attainment kvof:r a predetermined pressure in the'nelief' valve and. the precedingmeasuring valves.

3. An yautomaticlubricating.system comprising Aafseries of measuring va-lyes, affeed zline common thereto, avpump-for fchargingfsaid line,: a motor ,for driving said-pump; a p-ressure--relief valve inzfterposdzin ;said-, `lineflirectly ,in advance, ofisthe iinal valve in the series, whereby said nal valve is operative only on the attainment of a predetermined pressure in the relief valve and the preceding measuring valves, and pressure actuated means responsive to pressure in the final valve of the series for controlling the supply of energy to said motor.

4. An automaticV lubricating system comprising a series of measuring Valves, a feed line common thereto, a pressure actuated piston in each valve, a pump for charging said line, a motor for driving said pump, means connected directly to the piston in the nal valve of the series for controlling the supply of current to said motor, and a timed switch in the circuit of said motor.

5. An automatic lubricating system comprising a series of measuring valves of the type wherein lubricant is introduced under pressure and discharged under pressure by a fluid medium, each of said valves having an inlet for lubricant, an inlet for the pressure fluid medium, and an outlet adapted for connection to a bearing; a lubricant line connected to the lubricant inlets of said valves, a pressure line connected to the pressure fluid inlets of said valves, pumps for charging said lines, motors for operating said pumps, and pressure actuated means responsive to iluid pressure in the feed lines for successively controlling the circuits of said motors.

6. An automatic lubricating system comprising a series of measuring valves of the type wherein lubricant is introduced under pressure and discharged under pressure by a fluid medium, each of said valves having an inlet for lubricant,-an inlet for the pressure uid medium, and an outlet adapted for connection to a bearing; alubricant line connected to the lubricant inlets of said valves, a pressure line connected to the pressure fluid inlets of said valves, means for charging said lines; and pressure relief valves interposed in said lines directly in advance of the inlets of the final valve in the series, whereby said final valve is operative only on the attainment of predetermined pressures in the relief valves and the preceding measuring valves.

7. An automatic lubricating system comprising a series of measuring valves of the type wherein lubricant is introduced under pressure and discharged under pressure by a uid medium, each of said valves having an inlet for lubricant, an inlet for the pressure uid medium, and an outlet adapted for connection to a bearing; a lubricant line connected to the lubricant inlets of said valves, a pressure line connected to the pressure fluid inlets of said valves, pumping means for charging said lines, driving mea-ns for operating said pumping means, pressure relief valves interposed in said lines, and pressure actuated means behind said relief Valves and responsive to fluid pressure in said lines for controlling said driving means.

8. An automatic lubricating system comprising a series of measuring valves of the type wherein lubricant is introduced under pressure and discharged under pressure by a fluid medium, each of said valves having an inlet for lubricant, an inlet for the pressure fluid medium, and an outlet adapted for connection to a bearing; a lubricant line connected to the lubricant inlets of said valves, a pressure line connected to the pressure fluid inlets of said valves,

pumping means for charging said lines, driving means for operating said pumping means, pressure .actuated means responsive to fluid pressure in said lines for controlling said driving means, and a timed switch in the circuit of said driving means..

9. An automatic lubricating system comprising a series of measuring valves of the type wherein lubricant is introduced under pressure and discharged under pressure by a fluid medium, each of said valves having an inlet for lubricant, an inlet for the pressure fiuid medium, and an outlet adapted for connection to a bearing; a lubricant line connected to the lubricant inlets of said valves, a pressure line connected to the pressure fluid inlets of said valves, pumps for charging said lines, motors for operating said pumps, a pressure actuated member responsive to uid pressure in said lines, and means carried by said member for stopping the lubricant pump mo-tor and starting the other motor when said member is actuated.

10. An automatic lubricating system comprising a series of measuring valves of the type wherein lubricant is introduced under pressure and discharged under pressure by a fluid medium, each of said Valves having an inlet for lubricant, an inlet for the pressure fluid medium, and an outlet adapted for connection to a bearing; a lubricant line connected to the lubricant inlets of said valves, a pressure line connected to the pressure fluid inlets of said valves, pumps for charging said lines, motors for operating said pumps, a pressure actuated member responsive to fluid pressure in one of the valves in the series, means carried by said member for stopping the lubricant pump motor and starting the other motor when said valve is filled with lubricant and for stopping said other motor when said valve is filled with the pressure fluid medium.

11. An automatic lubricating system comprising a series of measuring valves of the type wherein lubricant is introduced under pressure and discharged under pressure by a fluid medium, e-ach of said valves having an inlet for lubricant, an inlet for the pressure fluid medium, and an outlet adapted for connection to a bearing; a lubricant line connected to the lubricant inlets of said valves, a pressure line connected to the pressure fluid inlets of said valves, pumps for charging said lines, motors for operating said pumps, -a pressure actuated member responsive to fluid pressure in said lines, means carried by said member for stopping the lubricant pump motor and starting the other motor when said member is actuated, and a timed switch in the circuits of said motors.

12. An automatic lubricating system comprising a series of measuring valves of the type wherein lubricant is introduced under pressure and discharged under pressure by a fluid medium, each of said valves having an inlet for lubricant, an inlet for the pressure uid medium, and an outlet adapted for connection to a bearing; a lubricant line connected to the lubricant inlets of said valves, a pressure line connected to the pressure fluid inlets of said valves, pumps forv charging said lines, motors for operating said pumps, a pressure actuated member responsive to iluid pressure in one of the valves in the series, means carried by said member for stopping the lubricant pump motor andv starting the other motor when said valve is lled with lubricant and for stopping said other motor when said valve is lled with the pressure fluid medium, and a timed switch in the circuits of said motors.

13. An automatic lubricating system comprising a series of measuring valves of the type wherein lubricant is introduced under pressure and discharged under pressure by a fluid medium, each of said valves having an inlet for lubricant, an inlet for the pressure fluid medium, and an outlet adapted for connection to a bearing; a lubricant line connected to the lubricant inlets of said valves, a pressure line connected to the pressure fiuid inlets of said valves, means for charging said lines, and a pressure relief valve interposed in said pressure line directly in advance of the final valve in the series, whereby said linal valve is operative only on attainment of a predetermined discharging pressure in the preceding measuring valves.

14. An automatic lubricating system comprising a series of measuring valves of the type wherein lubricant is introduced under pressure and discharged under pressure by a fluid medium, each of said valves having an inlet for lubricant, an inlet for the pressure iluid medium, and an outlet adapted for connection to a bearing; a lubricant line connected to the lubricant inlets of said valves, a pressure line connected to the pressure fluid inlets of said valves, pumping means for charging said lines, driving means for operating said pumping` means, a pressure relief valve interposed in said pressure line, and pressure actuated means behind said relief valve and responsive to fluid pressure in the nal valve in said lines for controlling said driving means.

15. An automatic lubricating system comprising a series of measuring valves, a feed line common thereto, a pressure actuated piston in each valve, a pump for charging said line, a motor for driving said pump, and means connected directly to one of said pistons for controlling the supply of current to said motor. y

16. An automatic lubricating system comprising a series of measuring valves, a feed line common thereto, a pump for charging said line, a motor for driving said pump, a pressure relief valve interposed in said line directly in advance of a valve in the series, whereby said valve is operative only on the attainment of a predetermined pressure in the relief valve, and pressure actuated means responsive to pressure in said valve in the series for controlling the supply of energy to said motor.

17. An automatic lubricating system comprising a series of measuring valves, a feed line common thereto, a pressure actuated p-iston in each valve, a pump for charging said line, a motor for driving said pump, means connected directly to one of said pistons for controlling the supply of current to said motor, and a timed switch in the circuit of said motor.

18. An automatic lubricating system comprising a series of measuring valves of the type wherein lubricant is introduced under pressure and discharged under pressure by a fluid medium, each of said valves having an inlet for lubricant, an inlet for the pressure fluid medium, and an outlet adapted for connection to a bearing; a lubricant line connected to the lubricant inlets of said valves, a pressure line connected to the pressure fluid inlets of said valves, pumping means for charging said lines, and actuated means responsive to fluid pressure in the feed lines for controlling said pumping means.

19. An automatic lubricating system comprising a series of discharge members, a feed line common thereto, a pressure actuated piston in each member, means for charging said line and members, and means connected directly to one of said pistons for controlling the operation of said charging means.

20. An automatic lubricating system comprising a series of discharge members, a feed line common thereto, means for charging said line and members, means responsive to pressure in said line for controlling the operation of said charging means, and a pressure regulator disposed in said line in advance of said pressure responsive means, whereby said pressure responsive means is operative only on attainment of a predetermined pressure in said line.

21. An automatic lubricating system comprising a series of dischargeV members, a pair of feed lines connected to each of said members and operable respectively for charging and discharging said members, means for supplying said lines and members with fluid, directing means interposed between said supply means and said lines for alternately directing iluid rst to one of said lines and then to the other, and means responsive to pressure in said lines for actuating said directing means.

22. An automatic lubricating system comprising a series of discharge members, a pair of feed lines connected to each of said members and operable respectively for charging and discharging said members, means for supplying said lines and members with fluid, directing means interposed between said supply means and said lines for alternately directing fluid first to one of said lines and then to the other, means responsive to pressure in said lines for actuating said directing means, and pressure regulators interposed in said lines in advance of said pressure responsive means, whereby said pressure responsive means is operative only on attainment of a predetermined pressure in said lines.

WILLIAM K. HAWKS. AARON J. JENNINGS. 

